You do not send a 1040X unless you have another reason to amend. The 8606 is a standalone form that can be mailed by itself.
You can download a blank form here:
https://www.irs.gov/pub/irs-pdf/f8606.pdf
https://www.irs.gov/pub/irs-pdf/i8606.pdf
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
